I am a newbie to LMDE and I only have some experience with Cinnamon when I was using Ubuntu.

I chose Cinnamon as the desktop environment but there are some problems with the buttons and views. The buttons are extremely ugly and they just look like the user interface under very old windows(window 98). There seems no way to customize them to better looking ones. (Please refer to the attachments as I find it hard to explain my problems very clearly.)

I have done some search but nobody seems to have such a problem. Could anybody please provide me some help?